Careful clearing of a head of cylinders and components клапанного the mechanism with the subsequent detailed check of their condition will help to define approximate volume of a forthcoming recovery work.

Strong overheats of the engine can lead to deformation of a head of cylinders and infringement of planeness of its interfaced surfaces (the Head of cylinders, item 2 see more low).

Cleaning

PERFORMANCE ORDER

Scratch out from interfaced surfaces of a head of the cylinders, all traces of a material of an old lining and hermetic, - try not to damage a surface.

Will essentially facilitate work application special размягчителя to which should impregnate preliminary stuck adjournment, — ask in shops of automobile accessories.

Remove from walls of water channels all traces of a scum.

Rigid wire brush carefully clean all accessible cavities and apertures. At strong pollution of channels it is necessary to charge head procleaning to experts.

"Banish" a tap approaching on the size each of болтовых apertures, having removed from a carving corrosion products, traces of old hermetic and having restored the damaged coils. In the presence of access to a source of compressed air, blow apertures, having removed from them a shaving and small dust.

At use of compressed air do not forget to put on goggles!

By means of solvent and a brass wire brush clear chambers of combustion of a deposit.

Wash out a head solvent and carefully dry it. Use of compressed air will allow to reduce essentially term of drying and will give the quality assurance of procleaning of badly accessible cavities and apertures.

For removal of traces of the deposit, procedures of cleaning essentially facilitating performance, it is possible to get any structures in many shops of automobile accessories. Remember that such means usually are chemically aggressive and should be applied with observance of corresponding safety measures, — strictly adhere to instructions of the manufacturers usually resulted on a label of container.

On engines SOHC wash out solvent levers of a drive of valves. Carefully dry components with application of compressed air and combine them in the organised order.

Use of compressed air will essentially facilitate procedure performance (do not forget to put on goggles).

Wash out in solvent and carefully dry клапанные springs, their plates and crackers of cutting locks, — try not to mix components.

Scratch out a great bulk of the valves of adjournment generated on surfaces, then a wire nozzle to an electrodrill definitively smooth out surfaces of cores and plates of valves — watch, that valves have not appeared are mixed.

Condition check

Before to make the decision on necessity of carrying out of machining of a head of cylinders, carefully study its condition. Having familiarised with the material stated in the present subsection, make the list of components requiring special attention.

Head of cylinders

PERFORMANCE ORDER

Attentively check up a head of cylinders on presence of traces of leaks of a cooling liquid, cracks and other damages. The tresnutaja head is subject to replacement without fail. In case of absence of confidence of definition of a condition of a head, it is necessary to send it for check in a car-care centre workshop. If repair is not obviously possible, replace a defective head.

By means of a measuring instrument of planeness and щупалезвийного type check up an interfaced surface of a head on presence of signs of deformation. If неплоскостность exceeds admissible value under specifications (Specifications see), it is necessary to send a head in проточку in a mechanical workshop.

A — the degree Estimation неплоскостности heads of cylinders is made on diagonals of each of interfaced surfaces B — Measurement of height of a head of cylinders is made from an interfaced surface to an interfaced surface

One of working parametres of heads of cylinders is their minimum admissible height (I) (from an interfaced surface to an interfaced surface) which should not be belittled in the course of machining (see Specifications).

Check up a condition of saddles of valves in each of combustion chambers. In case of revealing of cavities, cracks, traces прогара, it is necessary to subject a head to the special regenerative repair which performance lies out of limits of qualification of the average mechanic-fan and it should be entrusted to experts of car-care centre (the worn out directing plugs of valves should be preliminary replaced).

On diesel engines of 1.7 l SOHC there is a possibility of replacement of saddles of valves.

By means of special нутромера measure internal diameter of the directing plug of the valve. After extraction of a measuring instrument from the plug measurement by its micrometer is made. Measure also external diameter of a core of the valve. For the purpose of definition of size of a backlash of landing of the valve in the plug subtract from result of the first measurement result of the second. Compare the obtained data to requirements of Specifications.

At using нутромером enter it to the middle of length of the plug, then move upwards-downwards. Non-uniformity of resistance to measuring instrument moving testifies to presence конусности plugs. In the absence of confidence at definition of a condition of components do not hesitate to address for the help to experts.

The worn out plugs are subject to replacement. Old plugs are beaten out in combustion chambers with the help выколотки. Before installation new plugs should be cooled in the freezing chamber, then запрессовать in head drillings from outside a camshaft to ordered by norms (Specifications see) level выступания (if the data on height выступания the directing plug is not resulted, address for consultations to experts of a firm car repair shop of company Opel).

Sign of easing of landing of valves in directing plugs is occurrence of a dark blue smoke on an exit of system of release of the fulfilled gases.

On diesel engines of 1.7 l SOHC check up on presence of cracks and прогаровфоркамеры. Insignificant defects should not cause anxiety. Replacement of chambers is required only in cases deep прогаров, losses of the initial form or landing easing in head moulding. In the absence of confidence of condition definition форкамер do not hesitate to address for the help to experts.

Valves

PERFORMANCE ORDER

Attentively check up more low listed working surfaces of valves on presence of signs of non-uniform deterioration, deformations, cracks, cavities and traces прогара. Estimate degree of operation of cores of valves. Check up, whether there are no cracks in necks of cores. By rotation check up valves on a bend. Make sure of absence of cavities and signs of excessive deterioration of end faces. Revealing of any of the listed defects demands delivery of valves for regenerative repair in a car-care centre workshop.

Measure width of a cylindrical part (corbel) of a plate of each of valves. If the width of a corbel appears less than the stipulated value (Specifications see), replace the valve.

Klapannye springs

PERFORMANCE ORDER

Estimate degree of deterioration of face parts of each of клапанных springs, check up springs on presence of cavities. By means of an angular measuring instrument define free length and check up торцовкуклапанных springs. Compare results of measurements to requirements (Specifications see), — if the spring appears more shortly the bottom admissible limit, it is given and is subject to replacement. Check up also on conformity to standard requirements efforts developed by springs (performance of the given work to charge to experts of a workshop of car-care centre better). In the absence of confidence of definition of a condition of springs will replace them more correctly.

On petrol engines of a saddle of springs of final valves of 2.6 l SOHC are equipped by the duplicators facilitating freedom of rotation of valves in directing plugs. Turning manually, estimate a condition of duplicators, in case of revealing of jerks and signs закусывания make replacement of defective components.

Check up plates of springs and crackers of their cutting locks on presence of cracks and deterioration signs. It is necessary to replace all details being in a doubtful condition new in order to avoid development of defects in the future.

Camshafts, pushers of valves and assemblage коромысел with axes.

The description of procedures of check of a condition of the listed components see Removal, check of a condition and installation of components of a drive of valves. The condition estimation подшипниковых necks of camshafts should be made before the head will be sent a workshop for carrying out of service of valves. Presence on necks of scratches, задиров and other mechanical defects a head is subject to replacement without dependence from a condition of components клапанного the mechanism. At engine SOHC service it is necessary to check up also a condition коромысел a drive of valves with axes.

Replace all revealed defective components.

Grinding in of valves

PERFORMANCE ORDER

At considerable degree of deterioration of components of valves that is quite probable for the engine requiring major repairs, collect клапанные assemblages, establish them on the regular places in a head and pass to performance of procedures of service of valves.

If the external condition of valves is found satisfactory, measure by a micrometer diameters of their cores in several points. At revealing of an essential difference of results it is necessary to replace the valve.

For reliability перекрывания valves of accesses to combustion chambers in an engine operating time, at their installation it is necessary to grind in. Besides, grinding in allows to get rid of insignificant defects of interfaced surfaces. Necessary smoothness of a surface grew grey after carrying out of their machining can be reached only at use fine-grained притирочных pastes. Before use of coarse-grained pastes (in the presence of serious damages or прогаров saddles) consult with experts, — it is possible, saddle or valve replacement will appear a unique comprehensible way out.

Before to start grinding of valves establish a head on a workbench a surface interfaced to the block upwards.

Put a small amount притирочной pastes of demanded granularity on a surface of a saddle of the valve, then attach a sucker притирочного adaptations to an external surface of a plate of the valve. Rotary motions start to grind in the valve to a saddle, from time to time raising it for the purpose of paste redistribution. To facilitate a problem installation under a plate of the valve of a weak spring will help. At use of coarse-grained pastes try to achieve a dim matte surface of ground in details. Having received desirable result, clear surfaces of an abrasive and repeat procedure of grinding with application of fine-grained paste.

It is possible to consider grinding in finished when on working surfaces of a saddle and a plate there will be an indissoluble smooth matte ring. As soon as the demanded result will be reached, grinding in should be stopped.

Having finished grinding in of all valves, remove kerosene or solvent all traces of an abrasive and притирочной pastes.